diff --git a/pkgs/applications/networking/browsers/firefox/default.nix b/pkgs/applications/networking/browsers/firefox/default.nix
index 5a50bab09457..912a193eec9a 100644
--- a/pkgs/applications/networking/browsers/firefox/default.nix
+++ b/pkgs/applications/networking/browsers/firefox/default.nix
@@ -46,7 +46,7 @@ in rec {
       "--with-system-nss"
       "--with-system-libevent"
       "--with-system-libvpx"
-      # "--with-system-png" # <-- "--with-system-png won't work because the system's libpng doesn't have APNG support"
+      "--with-system-png"
       "--enable-startup-notification"
       "--enable-system-ffi"
       "--enable-system-hunspell"
@@ -66,7 +66,7 @@ in rec {
     inherit src;
 
     buildInputs =
-      [ pkgconfig gtk perl zip libIDL libjpeg libpng zlib bzip2
+      [ pkgconfig libpng gtk perl zip libIDL libjpeg zlib bzip2
         python dbus dbus_glib pango freetype fontconfig xlibs.libXi
         xlibs.libX11 xlibs.libXrender xlibs.libXft xlibs.libXt file
         alsaLib nspr nss libnotify xlibs.pixman yasm mesa
@@ -82,7 +82,7 @@ in rec {
 
     enableParallelBuilding = true;
 
-    patches = optional useSystemCairo ./system-cairo.patch; # probably in 22
+    patches = optional useSystemCairo ./system-cairo.patch;
 
     preConfigure =
       ''
@@ -136,7 +136,7 @@ in rec {
     enableParallelBuilding = true;
 
     buildInputs =
-      [ pkgconfig gtk perl zip libIDL libjpeg zlib bzip2 python
+      [ pkgconfig libpng gtk perl zip libIDL libjpeg zlib bzip2 python
         dbus dbus_glib pango freetype fontconfig alsaLib nspr nss libnotify
         xlibs.pixman yasm mesa sqlite file unzip pysqlite
         hunspell libevent libstartup_notification libvpx
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index d9e5242183f4..3ee03794796f 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -7390,6 +7390,7 @@ let
   firefoxPkgs = callPackage ../applications/networking/browsers/firefox {
     inherit (gnome) libIDL;
     inherit (pythonPackages) pysqlite;
+    libpng = libpng.override { apngSupport = true; };
   };
 
   firefoxWrapper = lowPrio (wrapFirefox { browser = firefoxPkgs.firefox; });